I'm not going to compare them with other bands, there are traces of jazz, folk, prog rock and funk. The band themselves call what they do "psychedelic funk rock" and that's not strange because of Canterburies past music scene (Soft Machine, Caravan and Camel). Raven Bush (great name by the way) is a nephew and heir of Kate Bush, a Kent girl herself. Their latest album "Sound Mirror" is a beauty with hits like Hometown Blues or this song "Garden of Time"
Here's some previous work, their album On and On
And here's the radio edit of my favourite song Hometown Blues, enjoy!